19.3 cm x 19.3 cm x 1.9 cm / 7.6 in x 7.6 in x 0.75 in
Napier's Bones was designed in 1617 by John Napier a Scottish Mathematician. In its day it was a wonderous device that simplified complex multiplication and other math processes such as long division and square roots. It was essentially the first calculator and was in common use for nearly 3 centuries.
This is something I find wonderfully elegant in understanding and explaining how basic math works. This can be a valuable tool for educators. Plus every math geek should have one to better understand his/her roots:))
Napier's Bones comes with 2 full sets of rods to increase its versatility. The more rods you have, the more complex and varied numbers you can manipulate. Also includes an attractive base and cover.